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Tiruchirappalli, India

Helan M.,Jamal Mohamed College Autonomous | Berchmans L.J.,CSIR - Central Electrochemical Research Institute
Materials and Manufacturing Processes | Year: 2011

Fine crystalline LiMn2O4 powders have been prepared by molten salt synthesis (MSS) at 500C, using an eutectic mixture of lithium chloride, lithium carbonate, and manganese acetate salts. Thermogravimetric and differential thermal analysis (TGA/DTA) measurements are performed to investigate the thermal decomposition behavior of the precursor salts. The single-phase cubic structure of LiMn2O4 is confirmed by X-ray powder diffraction analysis. The lattice parameter is found to be 8.1967 A. The molecular structure of the compound is studied using FT-IR and Raman spectroscopy. The chemical composition and the purity of the synthesized powders are determined using atomic absorption spectroscopy (AAS), energy-dispersive X-ray spectroscopy (EDAX), and carbon hydrogen nitrogen sulfur (CHNS) analyses. The magnetic behavior of the compound is examined using electron paramagnetic resonance (EPR) spectroscopy. The morphology of the powders is assessed by scanning electron microscopy (SEM). The average particle size of the powders is ranging between 10-20m. This investigation shows that pure crystalline lithium manganese oxide powders can be conveniently synthesized by molten flux method. Copyright © Taylor & Francis Group, LLC.

Arivazhagan M.,Aa Government Arts College | Meenakshi R.,Cauvery College for Women | Prabhakaran S.,Jamal Mohamed College Autonomous
Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy | Year: 2013

Quantum chemical density functional calculations were carried out for PFBN with the GAUSSIAN 09W using ab initio and Becke-3-Lee-Yang-Parr (B3LYP) functional. The observed FT-IR and FT-Raman vibrational frequencies are analyzed and compared with theoretically predicted vibrational frequencies. The geometries and normal modes of vibration obtained from DFT method are in good agreement with the experimental data. The first-order hyperpolarizability (β) of the investigated molecule was computed using DFT calculations. The calculated HOMO and LUMO energies shows that charge transfer occur within molecule. The influences of nitrogen on the geometry of benzene and its normal modes of vibrations have also been discussed. The UV-Vis spectral analysis of PFBN has also been done which confirms the charge transfer of PFBN. The chemical shifts of H atoms and C atoms were calculated using NMR analysis. © 2012 Elsevier B.V. All rights reserved.

Ahamed M.A.R.,Oxford Engineering College | Burkanudeen A.R.,Jamal Mohamed College Autonomous
Journal of Inorganic and Organometallic Polymers and Materials | Year: 2012

2-amino-6-nitro-benzothiazole and thiosemicarbazide with formaldehyde (BTF) terpolymer ligand and its metal complexes have been synthesized. The plausible structure of the synthesized BTF terpolymer ligand was elucidated on the basis of elemental analysis and spectral studies such as FTIR, UV-Vis, 1H and 13C NMR spectroscopy. Gel permeation chromatography (GPC) was used to determine the molecular weight of the terpolymer. The terpolymer metal complexes were analyzed by elemental analysis, molar conductivity measurements, and magnetic susceptibilities. The structure and geometry of the metal complexes were confirmed by various spectral techniques viz. electronic, ESR, FTIR and NMR spectroscopy. The morphology of the BTF terpolymer ligand and its metal complexes was examined using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The thermal decomposition behaviour of the terpolymer ligand and its complexes was determined using thermogravimetric analysis (TGA). Freeman-Carroll (FC), Sharp-Wentworth (SW) and Phadnis-Deshpande (PD) methods were used to calculate the thermal activation energy (E a), order of reaction (n), entropy change (ΔS), free energy change (ΔF), apparent entropy (S*) and frequency factor (Z) from the TGA data. Phadnis-Deshpande method was also used to propose the thermal degradation model for the decomposition pattern of the terpolymer ligand. The terpolymer ligand and its metal complexes were screened for its antimicrobial activity against chosen microbes. © 2012 Springer Science+Business Media, LLC.

Azarudeen R.S.,Oxford Engineering College | Burkanudeen A.R.,Jamal Mohamed College Autonomous
Research on Chemical Intermediates | Year: 2012

A novel chelating terpolymer resin has been synthesized from anthranilic acid, phenylhydrazine, and formaldehyde by condensation in glacial acetic acid. The structure of the chelating resin was clearly elucidated by use of a variety of spectral techniques, for example FTIR, and 1H and 13C NMR spectroscopy. The average molecular weight of the terpolymer resin was determined by gel-permeation chromatography. The empirical formula and empirical weight of the resin were determined by elemental analysis. The physicochemical properties of the terpolymer resin were determined. Scanning electron microscopy was used to establish the surface features of the chelating resin. The ion-exchange behaviour of the resin for specific metal ions, viz. Fe 3+, Co2+, Ni2+, Cu2+, Zn 2+, and Pb2+, was evaluated by a batch equilibrium method. The study was extended to three variations: evaluation of metal ion uptake in the presence of different electrolytes at different concentrations; evaluation of metal ion uptake at different pH; and evaluation of metal ion uptake at different times. Further, the reusability of the resin was also determined to assess the efficiency of the resin after a few cycles of sorption. From the results it was observed that the resin acts as an effective chelating ion-exchanger. © Springer Science+Business Media B.V. 2012.

Azarudeen R.S.,Oxford Engineering College | Subha R.,Oxford Engineering College | Jeyakumar D.,CSIR - Central Electrochemical Research Institute | Burkanudeen A.R.,Jamal Mohamed College Autonomous
Separation and Purification Technology | Year: 2013

Chelating terpolymer resin was synthesized from anthranilic acid and 2-amino pyridine with formaldehyde to remove the heavy metal ions present in the solutions. The synthesized terpolymer resin was characterized by spectral techniques such as FTIR, NMR (1H and 13C) and elemental analysis to elucidate the structure of the resin. The physico-chemical parameters have also been evaluated for the terpolymer resin. The surface morphology of the terpolymer resin without the metal ion uptake and with the incorporation of the metal ion was examined by scanning electron microscopy. The chelation ion-exchange property of the terpolymer resin was evaluated by batch equilibrium method for specific metal ions viz. Fe3+, Co 2+, Ni2+, Cu2+, Zn2+, and Pb 2+. The study was extended to three variations such as evaluation of metal ion uptake in presence of various electrolytes in different concentrations, evaluation of the distribution of metal ion uptake at different pH ranges and evaluation of the rate of metal ion uptake at different time intervals. The adsorption isotherm was evaluated by means of Langmuir and Freundlich isotherm models. The order of the kinetics was also determined and the resin follows first order kinetics which shows that physisorption may be involved in the ion-exchange process. From the results, it was observed that the terpolymer resin acts as an excellent cation-exchanger. Compared to the commercially available phenolic and polystyrene resins, the synthesized terpolymer resin showed an excellent ion-exchange capacity with the selected metal ions. © 2013 Elsevier B.V. All rights reserved.

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